APA
Khanna K. K., Khanna K. K., . (1977). Economics and commercial geography. New Delhi: Sultan Chand & Sons.
Chicago
Khanna K K, Khanna K K, . 1977. Economics and commercial geography. New Delhi: Sultan Chand & Sons.
Harvard
Khanna K. K., Khanna K. K., . (1977). Economics and commercial geography. New Delhi: Sultan Chand & Sons.
MLA
Khanna K K, Khanna K K, . Economics and commercial geography. New Delhi: Sultan Chand & Sons. 1977.